Mining apparatus



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` MINING APPARATUS Filed July ze, 1932 '5 sheets-sheet 5 Patentedl .July `9 E35 G APPATUS yCharles F. (isgood, Claremont. N. H., assigner to Sullivan Machinery Company, a corporation of Massachusetts Application JulyfZg, 1932, Serial No. 625,381

11s claims. (ci. gez-2s) 'I'his invention relates to mining apparatus. and more particularly to improvements in coal mining apparatus of the combined horizontal and shear cutter, wheel-mounted type adaptedA to operate from the mine trackway.

An object of this invention is to provide an improved coal mining apparatus. Another object is to provide an improved coal mining ap- Y paratus ofthe combined horizontal and shear cutter type. A further object is to provide an improved adjustable supporting structure for the' cutting mechanism of such an apparatus.v Yet another object is to provide an improved adjustable supporting structure whereby the kerf cutting mechanism may be positioned to cut kerfs in the coal face in any desired horizontal plane between the mine roof and the mine bottom and to cut vertical kerfs. Another object is to provide, in such an apparatus, improved adjustable kerf cutting mechanism operative to cut kerfs in the coal face in parallel planes either horizontally or vertically and in intersecting planes. Yet another object is to provide an improved mining apparatus of the Wheel-mounted, type adapted to operate while supported and guided by the mine trackway and having improved adjustable kerf cutting'mechanism whereby kerfs may be cut at or near the level of the mine bottom outside and below the level of the mine 'trackway, in any desired horizontal plane between the mine roof and the mine bottom and in vertical planes. A still further object is to provide in a mining apparatus of the aforesaid character improved adjustablekerf cutting mechanism whereby a vertical or shear-cut may be inserted in the coal face at `any desired location between the ribs of the entry. A still further object is to provide an improved tiltable mounting structure for the kerf cutting mechanism whereby the kerf cutter may be tilted to changeits angle in altitude, thereby to accommodate itself to a rolling or uneven mine bottom or pitching coal seam. Another object is to provide anvimproved coal mining apparatus of a truly universal character whereby an extremely wide range of adjustment of the kerf cutting mechanism is possible whereby kerfs may be cut in theA mine wall at practically any desired location. These and other objects and advantages of the invention will, however, hereinafter more fullyappear in the course yof the following description and as more particularly pointed out in the appended claims.

In the accompanying drawings there are shown for purposes ci illustration one preferrediorm.

and two modications thereof which the invention may assume in practice.

In these drawings,-

Fig. 1 is la plan View of the preferred illustrative embodiment of the improved mining apparatus.

Fig. 2 is a side elevational view of the apparatus shown in Fig. 1.

Fig. 3 is a horizontal sectional view taken substantially on line 3-3 of Fig. 2, with parts shown in plan.

Fig. 4 is a vertical sectional 'view taken sub-I Fig. '7 is a horizontal sectional view, with parts shown in plan, taken substantially on line 1 1- of Fig. 2l

Fig. 8 is a top plan view with cover platesv removed to illustrate structural details of the kerf cutter supporting and adjusting mechanism.

Fig. 9 is a transverse vertical sectional view taken substantially on line 9-9 of Fig. 4.

Fig. 10 is a longitudinally extending vertical sectional view illustrating a modied form vof adjustable supporting structure for the kerf cutter.

' Fig. 11 is a horizontal sectional view taken substantially on line lI-II of Fig, 10, with parts shown in plan to facilitate illustration.

Fig. 1-2 is a fragmentary side elevational view of a further modiiiedform of adjustable supporting structure for the kerf cutter.

Fig. 13 is a plan view of the mechanism shown in Fig. 12. i'

Fig. 14 is an enlarged detail sectional view taken substantially on line I4-I4 of Fig. 12.

Fig. l5 is a detail side elevational view of the mechanism shown in Fig. 14.

In the preferred illustrative embodiment of the invention shown in Figs. 1 to 9 inclusive, there is shown a coal mining 4apparatus of the combined horizontal and shear cutter, wheel-mounted type adapted to operate from the mine trackway and generally comprising a self-propelled portable base, herein in the form `of a truckl frame l mounted on wheels 2 adapted to run along a mine trackway 3. Y' Supported on the truck frame vl for rotative movement relative thereto about .a vertical axis is a horizontal turntable 4 having mechanism. Mounted on the forward portion of the frame 5 is the improved adjustable supporting structure, generally designated 6, for the` kerf cutting mechanism 1 and comprising a.

swingable arm structure l, a rotatable head 9 and a swingable kerf cutter support I0. Suitable mo- I for the kerf cutting mechanism 1, it will be noted that secured to the truck frame above the truck wheel axles is an annular turntable receiving frame II on which the circular turntable frame I2 is' mounted, the frame `II having an unstanding annular ange I3, and the frame I2 having v a depending annular flange I4, the flange I3 supporting a bearing sleeve I5 With whichthe flange |4 cooperates. `.also formed on the frame II is an inner annular nange I6 supporting a bearing sleeve I1 for an annular bearing member I8 secured to the bottom surface of the" turntable frame I2'. The mechanism for rotating the turntable 4 at a relatively low speed suitable for cutting and at a relatively high cutter positioning speed herein comprises a motor 20 mounted on the truck frame at the rear of the turntable structure and having its power shaft connected by a coupling 2| to a shaft 22 suitably journaled within a housing 23 mounted on the rearward portion of the truck frame. Fixed to the shaft 22 is a worm 24 meshing withva worm wheel 25 keyed to a sleeve 26 rotatably mountedon a transverse operating shaftv 21 likewise suitably 'journaled within the housing. 23 and within an upstanding -bearing bracket 28 herein formed integral'with the adjacent side of the truck frame. The sleeve 26 is adapted to drive through a plural speed, frictionally` controlled, planetary transmission mechanism generally designated 29, the shaft 21. This mechanism comprises a rotatable casing 30 frictionally controlled by a brake band 3| regulated by a hand wheel 32. A sliding clutch element 33 controlled by a clutch shipper member 34 is employed for attaining a relatively high and a relatively low speed, this clutch member being alternatively engageable with the high and'low speed terminal members 35 and '36 respectively of the transmission mechanism. As the specic structure of this planetary transmission mecha- The shafts 4| and 45 are suitably journaled within the truck frame, and the shaft 45 has key'ed thereto and drives a spur gear. 45 meshing with a large spur gear 41 herein formed integral with the depending flange ,I4 of the rotatable frame |2'ofl'the turntable 4 (see Fig. 4). -It will .thus be seen that when the bevel Vgear 39 is connected to the shaft 21 and the clutch member 33 is operated in an appropriate manner, the turntable 4 maybe rotated at either a relatively high or a relatively low speed under frictional control of the brake band 3| of the planetary transmission 29. The motor 20 is herein ofthe reversible electric type, and it is accordingly evident that the turntable may be rotated in either of opposite directions at either a high speed or a low speed. When the turntable is disconnected from its rotating mechanism it may be locked against rotav tion by meansof a slidable locking element 45 (see Fig. 1) guided in a bracket 49 attached to the turntable frame I and engageable with the teeth of the gear 41 formed on the rotatable turntable frame.

'I'he motor 20 and the lplanetary transmission mechanism 29 also constitute driving means for the truck wheels to propel the apparatus along the mine trackway at either arelativelyhightransport speed or at a relatively low cutting speed. This truck wheel driving mechanism comprises a chain sprocket 5,0 journaled on the shaft 21 and connectible thereto by the jaw clutch member 31, and this sprocket is connected by an endlesschain 5| to a chain sprocket 52 flxed to the rear truck wheel axle. A truck wheel brake is provided and comprises a brake drum 53 keyed to the rear truck wheel axle and with which coope rectlons at either speed whenever the clutch` member 31 is operated to connect the 'truck driving member 50 to the shaft 21, and that thetruck wheel driving speeds may both .be frictionally controlled by the brake band 3|.I When the clutch member 31 is-in the .position shown in Fig. l, i. e. its -neutral position, both the turntable rotation and the truck wheel drive are disconnect- Y ed from the motor 20.

Now referring to the kerf cutting mechanism, and more particularly to the improved adjustable supporting structure therefor, it will be observed that housedwithin the turntable frame 5 is a horizontal motor 60, herein preferably of the reversible electric type, 'having the forward end of its power shaft 5I operatively connected to the devices for operating and adjusting the kerf cutting mechanism. In the present construction there are formed integral with the forward portion of the turntable frame 5 parallel, forwardly projecting frame, portions 52, B2, and journaled within these frame portions is a transverse hinge shaft 53. Pivotally mounted at its rear end on this hinge shaft is a main supporting arm 54, and

this arm has rotatably mountedat its forward end about an axis extending longitudinally of the arm and at right angles to the hinge shaft axis, the rotatable head 9. In this construction, -formed integral with the arm structure at its outer extremity is a circular framev 65 arranged in a trans- .verse plane perpendicular to the longitudinal axial line of the arm and the head axis, as shown in Fig. 4. Secured to this circular frame 55 is an annular'retaining'and bearing sleeve 55 having an inwardlyl directed flange 61. Between this ange and a shoulder l68. formed on the circular frame 65 there is rotatably mounted a sleeve 59 which herein forms a rotatable support for the head 9. 'I'his sleeve 59 is secured to the frame 15 of the `head 9, and this framel10 comprises parallel outwardly projecting frame portions 1|, 1| extending parallel to and equidistant from the aoomov axial line of the rotatable head 9. Supported within these frame portions 1|, 1| is a transy verse hinge shaft 12 arranged with its axis perpendicular to and intersecting the axial vline of the rotatable head, and pivotally mounted at its rear end on thishinge shaft is the kerf cutter supporting frame l0. The arm 8 and the kerf cutter support l are independently swingable about their respective axes, and the lhead 9 is rotatable relativevgto the armv 8 throughv improved devices which will now be described. As shown in 3, connectible to the forward end of the motor power shaftl', as by a multiple disc clutch 13, is a worm l14nrleshing with worm wheels 15 and 16 and simultaneously driving the latter in the same directiong" vThese worm wheels are xed to parallel vertical shafts 11 and 18 respectively, suitably journaled within the turntable frame 5. Keyed to the upper ends of these shafts are spur gears 19 and 80, and these gears mesh respectively with spur gears 8| and 82 xed to parallel vertical shafts 83 and 84, the latter likewise being suitably journaled within the .turntable frame 5.

Keyed to the shafts 83 and 84 respectively are worms 85 and 86 meshing with worm gear teeth 81 vformed on segmental portions 88, 88 integral with the arm 8 and overlapping the frame portions 62, 62 of the turntable frame 5. It will thus be' vments on the arm 8 may be driven to swing the arm either upwardly or downwardly, depending upon the direction of motor rotation. If desired,'however, la suitable reversing mechanism may be provided in the drive so that the arm may be swung eitherupwardlvor downwardly without reversal of the motor. Keyed to the'- forward end of the motor power shaft 6| is a bevel gear 90 meshing with a bevel gear 9| loosely mounted on the hinge shaft 63.v Meshing with the bevel gear 9| is a bevel gear 92 i'lxed to a shaft 93 suitably journaled within and extending longitudinallyof the arm 8. lIi'he ldevices for rotating theghead relative to the ann 8 are-driven by the shaft 93 and herein comprise a spur gear 94 keyed to the shaft 93 (see Fig. 4) i and meshing with a spur "gear 95 keyed to a parallel shaft 96, the latter likewise suitably journaled within the arm 8.. Fixed to the forward end of the shaft 96 and driven thereby is a bevel pinion 91 meshing,

-as shown in Fig. 9, with reverse bevels 98 and '99.

These reverse bevels are selectively connectible by suitable multiple` disc clutches |00, |0| to a transverse shaft |02 to effect drive of the latter in opposite directions. The shaft |02 is arranged transversely of the arm 8 and issuitably journaled therein, as shown. Keyed to the shaft |02 and driven thereby is a worm |03 meshing with a worm wheel |04 keyed to a shaft |95. A'l'.his shaft is arranged parallel with the shaft 93 and is likewise suitably journaled within the arm 8, as shown in Fig. 3. Keyed to the forward en d of the shaft IIS and driven thereby is a spur gear |06 meshing with the teeth of a large internal gear |01,- herein formed integral with the sleeve 89 of the rotatable head. It will thus be seen that depending upon which one of the disc clutches |00, |0| is applied, the head 9 may be rotated relative to the arm 8 at a cutter` positioning speed in either of opposite directions while the transmission shaft 93 rotates continuously in the same direction, the shaft 93 also constituting a drive shaft for the kerf cutter, as will hereinafter be described. As shown in Fig. 6, the forward end of the transmission shaft 93 is journaled within a bearing carried within the head frame 10, and keyed to this end of the shaft isa bevel gear |09 meshing with a. bevel gear H0 loosely mounted on the hinge shaft 12 (see Fig. '1). The bevel gear ||0 is'xed to a sleeve likewise journaled on the hinge shaft, and fixed to this sleeve and driven thereby is al'spur gear 2 meshing with an intermediate gear ||3 journaled on a transverse idler shaft l I4 mounted within the parallel frame portions 1|, 1| of the head frame 10. The gear ||3 meshes with a spur gear H connectible by a multiple disc clutch |I6 to a shaft ||1 herein arranged transversely of the head frame and suitably journaled therein. Keyed to the shaft ||1 at the opposite ends thereof are worms H8, ||9 meshing respectively with worm wheels |20 and |2| keyed to shafts |22 and |23 respectively. These shafts are herein arranged at right angles to the shaft H1 and are likewise suitably journaled within the head frame 10. Keyed respectively to the shafts |22, |23 are worms |24 and |25 (see Fig. '7) meshing with worm gear segments |26, herein formed on parallel frame portions |21, |21 herein overlapping the frame portions 1|, 1| and formed integral with portions |21, |21 receiving the outer ends of the hinge shaft 12, thereby to form a pivotal mounting for the kerf cutter support I0. It will thus be evident that, when thc'disc clutch I6 is applied, the kerf ,cuttersuppo'rt |0 may be swung about its pivotal axis relative to the rotatable head 9 in either direction, depending upon the direction of motor rotation. It will be evident, however, that if desired a suitable reversing mechanism may be provided to enable swinging of the kerf cutter support inleither direction relative to the head without reversal of the motor. will be alsov noted that the worm gearings for swinging the arm 8, for rotating the head 9 and for swinging the kerf cutter support |0 are herein of the self-locking type, and lock automatically the elements adjusted thereby when disconnected from their respective driving means. 'It will further be noted that the gearings for swinging the arm 8 and for swinging the kerf cutter support l0 relative to the head 9 may beso proportioned that when the arm 8 is swung in one direction the support |0 is swung in the opposite direction at.

such speed as to maintain the kerf cutter at all times in a substantially horizontal plane, and that the slow speed of turntable rotation. may be also so proportioned with the swinging speed of the support 0 that when the kerf cutter is in a vertical position it may be swung horizontally while the kerf cutter at all times remains parallel to a vertical plane.

Now referring to the improved mechanism for driving the kerf` cutting mechanism and for lswinging the kerf cutter about its pivot relativev .|35 of a usual design to the shaft |34', and keyed to the outer end of the shaft |34 and driven thereby is a sprocket |36 which.- engages Vand drives an endless cutter chain |31 mounted for circulation about the margin of a cutter bar |36. This cutter bar is attached to a cylindrical supporting frame |39 rotatably mounted in a bore |46 formed in the frame |4| of the swingable kerf cutter support I6. 'A thrust ring |42 attached to the frame |4| serves to retain the frame |39 in its bore.

` Now referring to the mechanism for effecting swinging of the cutter bar |36 about its pivotal axis relative to the swingable support |6, it will be noted that ilxed to the shaft lul'l'd driven thereby is a spur gear |44 meshing with-spur gears |45 and |46 respectively. 'Ihe gears |45 and L46 are xed to parallel shafts |41 and |48 herein arranged parallel with and .at opposite sides of the shaft |34'and likewise suitably journaled within the support I6. Keyed to these shafts respectively are worms |49 and |56 having teeth of different inclination and meshing respectively with wormwheels and |52. The worm wheel I5| ,is herein a slow speed worm wheel, while the worm wheel I 52 is a high' speed worm wheel', and these worm wheels rotate at 4speeds suitable to effect swinging of the cutter bar at a relatively lo'w speed in one direction and at a relatively high bar positioning speed in the opposite direction. These worm wheels are alternatively connectible by multiple disc clutches |53 and |54 respectively to a transverse shaft |55, herein arranged parallel with the hinge shaft 12 e and suitably journaled withinthe swingahle cutter `support I6. Keyed to the shaft' |55 is a worm |56 meshing with a worm wheel |51`keyed to a transverseshaft |56. This shaft is herein arranged parallel with the shaft |34 and is likewise suitably journaled within the cutter support I6., and this shaft has connectible thereto by a "sliding clutch |59 aspur pinion |66 meshing with Figs. 1Q and 1l is similar to the preferred formdescribed above with the exception that the rotatable head is mounted in advance of the pivotal axis of theswingable kerf cutter support so that thehead swings with' the-kerfcuttervsupport Vao relative to the swingable arm structure. In this 'form of the invention thelswingable arm which corresponds to the arm l8 is numbered |65, and

the mechanism for swinging this arm is identical to the mechanism for swinging the arm 6, and

.therefore illustration and description thereof are thought unnecessary. .'Ihe arm |65 has formed integral therewith forwardly projecting' parallel frame portions |66, |66, and journaled within these frame portions is a transverse hinge shaft |61 arranged with .its axishorizontal andparallel 4with the hinge shaft 63. Pivotally mounted at its rear end on this hinge shaft isa swingable support |68, and this support" has rotatably mounted thereon a rotatable cutter head |69.

' TheY mechanismffor swinging .the suppdrt |66 nsk about its pivotal axis relative to the arm |65 comprises la.v bevel gear |16 meshing with the bevel gear 9| and keyed to a shaft |`1| suitably journaled within the arm |65. Keyed to the forward end of this shaft is a bevel gear |12 meshing with a bevel gear |13 loosely journaled on the hinge shaft |61. Secured to and driven by the bevel gear |13 is a hollow shaft |14, and fixed to this shaft is a spur gear |15 mhing with an intermediate gear |16 journaled on an idler shaft |11 suitably supported within the frame ,segments |65, |85 formed o n segmental portions |86 integral with the support |68 and arranged parallel with and overlapping the frame portions I ,66. 'It will thus be seen that the support |66 may be swung in either direction about its plvotal axis relative to the arm |65, depending upon the direction of rotation of the worms |64, |64.

As previously mentioned, the cutter head |69 is rotatably mounted on the swingable frame or support 'I 66, and the mounting therefor comprises a cylindrical bearing sleeve -|88 having rotatably mounted thereon a cylindrical supporting frame |89 for the head. This supporting frame issttached to the cutter head frame |69 and has an inwardly directed annular retaining'ange |96 cooperating with the bearing sleeve |66 vand an annular flange 9| formed .integral with the frame |68. Mounted on the cutter head frame |69 for rotation about an axis atright angles to the axis of the cutter head is a cylindrical supporting frame |92 rotatably mounted in a bore |93 formed in the cutter head frame. A thrust ring |94 attached to the cutter head frame serves to retain the frame |92 in its bore. Attached to the frame |92 is a support or hanger |95 which carries the cutter bar |36. Mounted for orbital movement on themargin of the cutter .bar |38 is the endless cutter chain |31, this cutter barv structure being identical to that described above in the preferred embodiment of the invention.

The mechanism for actuating the cutter chain comprises a bevel gear |91 meshing with the bevel gear |13 and driven thereby. The bevel gear |91 is fixed to a shaft |98 extending through the cutter head frame along the axis of the cutter head and suitably journaled within the cutter head frame. Keyed to 'the forward end of the shaft |96 is a bevel pinion |99 meshing with a large bevel gear l2 66. The bevel gear266 is connectible by .a sliding clutch 26| to a transverse shaft 262 suitably journaled within the head .frame and driving a chain sprocket 263 which engages and drives the cutter chain |31. 4

'- The mechanism for rotating the cutter head about its'axis and for swinging the vcutter bar will now be described. Keyed to the shaft 262 is a bevel pinion 265 meshing with 'reverse bevels 266 and 261. These reverse bevels are alternatively connectible-by multiple disc clutches 268 and 269 of the usual design, to a transverse shaft 2|6 suitably journaled within the cuttei head lframe. Con'nectibleto this shaft, as by a sliding clutch 2| l, is a worm 2| 2 meshing withv a worm wheel 2|3 fixed to a shaft 2|4, herein arranged parallel with the shaft 262 and likewise journaled in the cutter head frame. Connectible to the shaft 2 I3, as by a clutch similar to the clutch |59 heretofore'referred to, is aspur pinion 2|5 meshing with the teeth of a large internal gear 215, herein formed integral with the cylindrical supporting frame |92 for the cutter bar |38. It will thus be seen that depending upon which disc clutch 203, 289 is applied, the cutter bar may be swung about its pivot at a speed appropriate for cutting in either of opposite directions. The mechanism for rotating the cutter head about its axis herein comprises a worm 2|1 connectible, as by a sliding clutch 2 I 8, to the shaft 2 I (i and meshing with a worm wheel 2 |9 fixed to a. longitudinally extending shaft 229 herein arranged parallel with the shaft |98 and suitably journaled within the cutter head frame. Fixed to the rear end of the shaft 220 isa spur pinion 22| meshing with the teeth of an internal gear 222 herein formed integral with the cylindrical head'support |88. It will therefore be evident that the cutter head may be rotated about its laxis in either of opposite `directions under the control of vthe friction clutchesv 208, 209. The worm gearings of the bar swinging mechanism and of the head rotating mechanism are self-locking, and upon release of the controlling clutches maintain automatically the cutterv bar and head intheir positions of adjustment. The gearings for swinging the arm |65 and for swinging thecutter head support |88 relative to the arm are so proportioned that when the arm is swung in one direction, the support j may bey swung simultaneously in the opposite direction, thereby tomaintain the cutter bar at all times substantially parallelto a horizontal plane.

In the modiiicationshown in Figs. 12 to 15 l inclusive, theI arm swinging structure and the turntable and truck mounting are identical to the forms above described, but in this form of the invention the driving connections between the motor 60 on the turntable and the devices for rotating the head and swinging the cutter bar are eliminated, and `in this'instance the head rotating and kerf cutter swinging devices are driven by a motor 230 carried .within a support 23| on which the cutter head is rotatably mounted. Pivotallyl mounted on the hinge shaft 53 is an arm 232, herein in the form of a yoke having its side'arms 233, 233 straddling the motor support, as shown in Fig. 13. Arranged parallel with the arm 232 is a parallel motion arm-234, also in the form vof a yoke, pivotally connected at 235 Y to the turntable frame and at 236 to the motor support 23|; the arms 232l and 234 cooperating to form a parallel motion device' for maintaining the cutter head axis at lall times substantially par'- allel to a common straight line'during swinging of the arm structure. The power shaft 231 of the motor 230 corresponds to the drive shaft |98 oi.v the form of the invention shown in Figs. and

11, and the mechanisms driven by this shaft for rotating the cutter head and for-'swinging the ,cutter bar about its pivot and the pivotal mountings fox` the head and cutter bar are identical to those described Vin that form of the invention,

and therefore further description and illustration thereof'are deemed unnecessary. As shown most clearly in Fig. 14, the ends of the hinge shaft 235 which project within the bearingA portions Aat the sides of the arm are eccentric relative purpose of puttingthe relations of the four bearings of the parallel arm ystructure out of true sumcient to intentionally slightly 4tilt the cutter head out of parallel relation withv the longitudinal axial line of the turntable frame 5; this beingat times desirable when there is a slant in the lupper or lower 4face 'of the vein of coal, or if there is a slight slant in the track on which the apparatus is guided. Adjustment of the hinge shaft 235 is, in this instance, effected manually by that the cutter bar may be tilted about an axis f transverse to its length, as desired, the tilting mechanism above described corresponding to the tilting mechanisms for the cutter bar supports of the preferred form and modication above described.

.The mode of operationof the-embodiment of the invention shown in Figs.1 to 9 inclusive is as follows: The apparatus is propelled along the mine trackway at a relatively high transport speed I through the planetary transmission 29 driven by the motor 20, it being understood that at that time the cutter bar is in the full line position shown in Figs. 1 and 2. When the working face is reached, the high truck .wheel drivepis disconnected from the motor by releasing the friction band 3| and sliding. the clutclrmember 33 into its neutral position. If it is desired to make a'horizontal out at or near the level of the mine bottom in front of the end of the trackway in 4accordance with the arcwall method, the disc clutches 13 and respectively controlling the worm gearings 85, 88, 81 and |24, |25, |28 of the swinging mechanisms for the arm 8 and the bar support I0 are applied,'thereby swinging the parts into the lower dotted line position in Fig. 2, the

bir support I 0 swinging upwardly about its pivot as the varm moves downwardly about its pivot, thereby to move the cutter bar into the horizontal bottom cutting-position shown. The fast speed controlling clutch l 54 oi the bar swinging mechanism is then applied, and the cutter bar |38 is swung laterally from left to right until its tip end is located adjacent the right hand rib of the entry, the clutch |54 thereafter being released. The operator then operates the sliding clutch |35, connecting the cutter chain |31 to its drive. With the parts thus disposed the clutch member 33 of the planetary transmission 29 is shifted to connect the low speed gearing thereof to the motor 20, and upon connection of the clutch 31 the truck wheels are driven to-propel the apparatus bodily along the mine trackway at a slow cutting speed to eifect sumping of the cutter bar beneath the coal. After the completion of the wheels against movement, and the slow speed clutch A| 53 of the bar swinging mechanism is applied, thereb'y effecting swinging movement of the cutter bar about its pivot fromits position adjacent the right hand rib transversely across the coal face to a position adjacent the left hand rib, the clutch |53 thereafter being released.' 'Aiter the completion ofthe swinging cut, the motor 20 v sumping cut, the clutch members 38 and 31 are released, the .brake 53 set, holding the truck is reversed,and upon 'connection of the clutches v'33, 31 the apparatus .is propelled bodily rearwarcily along the mine' trackway to effect-with- .f-drawal of the cutter bar from beneath the coalface. The cutter' bar and its adjustable supporting structure are then returned to the full.

line position indicated in Figs. 1 and 2, and upon connection of the fast speed drive oi' the planetary transmission, the apparatus is propelled bodily rearwardly along the trackwayat a high transl port speed to another working place.

` swung horizontally at a high positioning speed from the central full line position' shown in Fig.

lto a position wherein the pivot of the cutter bar lies outside of the trackway. During horizontal swinging movement of the turntable relativeto the truck, the cutter bar may be swung simultaneously about its pivot in the opposite direction under the control of the clutch |53 of the cutter swinging mechanism until the tip end of the cutter bar assumes a position adjacent the right hand rib at a less angle than the angle ofthe pivoted arm structure relative to theA rib. When the parts are thus disposed with the bar pivot lying outside the mine trackway, the operator releases the clutches |53, Il and 33, and

- upon application of the clutches 13 -and I I8 of A, justable arm structure relative thereto.-

lturntable rotation and bar swinging mechanisms the mechanisms for swinging the arm I vand b ar support l0, the arm 8 is swung downwardly about its pivot while the support I issimultaneously swung upwardly until the parts assume the lower dotted line position shown in Fig. 2 with the cutter bar at the level of the mine bottom outside the mine trackway. When the parts are thus disposed the turntable is locked against rotation and thereafter the truck wheels are driven from the motor 20 through the planetary transmission 28 to propel the apparatus bodily along the mine trackway at a slow cutting speed to e'ect sumping of the cutter bar beneath the coal face. The brake 53 is then setto hold the truck wheels stationary, the turntable lock released, and the turntable rotation mechanism is operated to effect rotation of the turntable at av relatively slow speed to effect swinging of the adjustable arm structure for the cutter bar laterally from right to left. Upon initial swinging movement of the arm-structure, the cutter bar is swung about-its lpivot in the opposite direction until the parts assume a straight line position 1 wherein the cutter bar lies in a vertical plane passing through the bar pivot and turntable axes. After the cutter bar has beenstraightened up, turntable rotation is continued, thereby -swinging the cutter bar about the turntable axis from the right hand rib until the tip end of the cutter bar lies adjacent the left hand rib. After the tip end of the cutter bar has reached the left hand rib, the cutter bar is again swung about its.

pivot in a direction opposite from the direction of turntable rotation while rotation of the turntable 4 is' continued, the turntableand cutter bar swinging simultaneously in opposite directions at that time until they assume an angular position with the cutter bar disposed at a less angle relative to the left hand rib than the angle of the ad- The are then disconnected from their drives and the turntable lock connected, the brake 53 released, and thereafter the apparatus is propelled bodily rearwardly along the mine trackway at a slow speed to eifect withdrawal of the cutter bar from beneath the coal. After the completion of the bottom cut beneath the coal, the parts are again returned to their transport position, as indicated in full lines in'Figs. 1 and 2, and the apparatus propelled to another working place.

A horizontal kerf may be cut at or near the level of the mine roof by applying one or the other of the friction clutches |00, IDI of the head rotating mechanism to eifectrotation of the cutter head Q from the full line position shown in Fig. 2 to a position where'in the cutter bar overlies the bar support, the cutter bar moving through an arc of a circle from its lower position to its upper position. When the parts are thus disposed the clutches controlling the mechanisms for swinging the arm 8 andthe bar support l0 about their respective pivots are operated to eil'ect swinging movement of the arm upwardly to the upper dotted line lposition shown in Fig. 2, the bar support I0 swinging downwardly as the arm swings upwardly until the parts assume the top cutting position shown. The cut.- ter bar is then sumped in, swung transversely in its plane and withdrawn from the coal face in accordance with the usual arcwall method of cutting.. 'f

It will be noted that during any of the horizontal cutting operations above described, for instance when it is desired to cut a rolling or uneven bottom, the cutter bar may be tilted about transverse and longitudinal axes, i. e. about the axes of the head 9 and the bar support I0, to change its angle in altitude. For instance if it is desired to tilt the tip end of the cutter bar upwardly or downwardly, this may be accomplished simply by swinging the' bar support I0 upwardly and downwardly about its pivotal axis, while if it is desired to tip the cutter bar edgewise, the head 9 is-rotated about its axis.

A shear`or vertical cut y be inserted in the coal face by applying one r the other'of the averse frictions |00, |0| of the head rotating mechanism, thereby rotating the head 9 about its axis to bring the cutter bar into a position to swing vertically. During the shearing operation, the cutter bar is rst sumped in, then swung downwardly in its plane and thereafter withdrawn from the coal face in a manner similar to that described above in connection with horizontal cutting in accordance with the usual arcwall method. It will further be noted that by rotating the turntable and simultaneously swinging the bar support ||I about its pivot, the cutter barmay bevpositioned to cut vertical kerfs at any desired location between the center of the entry andeither rib, one shearing position being indicated in dotted lines in Fig. A1. When the parts are in the dotted line position shown in Fig. 1 the arm 8 may be swung upwardly to position the tip end of the cutter bar at the roof and the apparatus may then be propelled bodily along the trackway to effect sumping of the cutter bar within the coal face. After the completion of the sumping cut, the arm may be swung downwardly to move the cutter bar in an arcuate pathv about the arm axis as a pivot to cut an upright-slightly curved kerf in the coal face from a point adjacent the mine roof to a point at the mine floor. Thereafter the cutter bar may be moved rearwardly to eiect its withdrawal cut by along the trackway. By swinging the bar support I6 about its vertical pivot from the dotted line position shown yin Fig. 1 to an angularly disposed position with the tip end-of the cutter 5 bar adjacent the left hand rib, a similar upright slightly curved kerf may be cut in the rib. By swinging` the arm to the opposite side of the apparatus a similar cut may be inserted-in the tal cuts in the same manner as in the form ofv the apparatus described above.` Therefore detailed description of these methods of cutting is .unnecessary However, in thisvform of the apparatus, shear cuts can be inserted in the coalface when in positions only at either side of the head axis, it being impossible with this form -of construction to insert shear cuts at any desired location between the ribs of the entry. In this form of the invention the arm |65 is swung about its pivot whilethe frame |68 and cutter headl |69 supported thereby are simultaneously swung in the opposite direction, the cutter head swinging with the support |68 in this form of the invention instead of with the swingable arm |65, as in the preferred form of the invention. -.The cutter bar is moved into its vertical cutting position by rotating the cutter head |69 relative to the support |68. `The operation of the form of the invention shown in Figs. 12 to 15 inclusive is identical to that of the modification shown in A, Figs. 10 and 11, and therefore further detailed illustration and description thereof are deemed unnecessary.

-As a result 'of this invention, it will be noted that an improved coal mining apparatus is provided having improved adjustable kerf cutting mechanism whereby horizontal kerfs may be cut -at or near the level of the mine bottom either in front of or outside and below the level of the mine trackway, horizontal cuts at any desired location between the mine roof and mine bottom, and vertical cuts may be cut at any desired location between the ribs of the entry. It will further be, noted that by the provision of the improved adjustable supporting structure for the kerf cutting mechanism, the cutter bar may not only be positioned at any desired location between the mine roof and mine bottom and the ribs of the entry, but may also be tilted about longitudinal and transverse axes, to change its angle in altitude, thereby to accommodate itself to a rollingl or uneven bottom or pitching coalr seam. It will still further be noted that an' improved coal mining apparatus is provided wherein the adjusting mechanism for the kerf cutter is ex-v tremely iiexibl'e and has a wide range of adjustment, it being possible to operate the apparatus as a bottom cutter, top cutter, center cutter.

shear cutter and slabbing machine, thereby enabling the apparatus to accommodate itself to practically every mining condition encountered. 'Ihese and other uses and advantages ofthe improved mining apparatus will be clearl'y apparent,

modications of the same are shown for purposes of illustration and that the invention may be modified and embodied -in .various other forms without departing from its spirit or the scope of the appended claims.

What I claim as new and ldesire to secure by Letters Patent is:

l. In a mining, apparatus, a portable base, a

horizontal turntable on said base, an arm structure extending lforwardly in advance of said base and pivotally mounted at its rear end on the for- Ward edge of said turntable to swing in a vertical direction relative thereto, a kerf cutter support pivotally mounted on the outer extremity of said arm structure to swing relative thereto about an axis parallel with the arm structure pivot axis, a kerf cutter c arried by said support, devices for swinging said arm structure relative to said turntable, and devices for swinging said kerfcutter support relative to said arm structure to vary the plane of cut thereof, said cutter support being swingable relative to said arm structure while the latter remains stationary.

2. In a mining apparatus; a portable base, a horizontal turntable on said base, an arm pivotally mounted on said turntable to swing in a vertical direction relative thereto, a head mounted on said arm to rotate relative thereto, a kerf cutter support pivotally mounted on said rotatabl head,

to maintain the kerf cutter always'in a substank tially horizontal position.

4. In a mining apparatus, a portable base, a horizontal turntable on said base, an arm pivotally mounted on said turntable to swing in a vertical direction relative thereto, a head' mounted on said arm to Arotate relative thereto, a kerf cutter support pivotally mounted on said rotatable head, and a kerf cutter pivotally mounted on said cutter support to swing relative thereto, said head being rotatable relative to said arm Ato adjust the kerf cutter into horizontal and vertical cutting positions. i

5. In a mining apparatus, a portable base, an arm structure mounted on said base to swing horizontally and vertically relative thereto, the axis of vertical swinging movement of said arm structure located in advance of the axis 'of horizontal swinging'movement thereof, a kerf cutter, and an adjustable supporting structure carried by said arm structure and adjustable therewith'for adjusting said kerf cutter into horizontal and vertical cutting positions and for tilting said kerf cutter lengthwise relative to said ,armv structure while the latter is stationary to change the plane of cut. 6. In a mining apparatus: a wheel supported base adapted to run along a mine trackway, a

' horizontal turntable mounted on saidbase, a kerf cutter, and an adjustable supporting structure for 'said kerf cutter, said turntable and supporting structure being adjustable to position said kerf cutter to cut horizontal kerfs at any desired location between the mine roof and mine ,-bottom, to

:base adapted to run along a mine trackway, a

wh'orizontal turntable on said base, a kerf cutter,

v'an adjustable supporting structure intervening said turntable and kerf cutter and adjustably ymounted on said turntable, said turntable and supporting structure being adjustable to move said kerf cutter into horizontal cutting positions at any desired location between the mine roof and mine bottom and said supporting structure including supporting means adjustable bodily relative to said turntable and includingsupporting table and supporting structure also being adjustvable to position the kerfctter to cut a horizontal elements adjustable about longitudinal and transverse axes to move said kerf cutter relative to the turntable into a vertical cutting position and to tilt the kerf cutter, when in horizontal cutting position, about a transverse axis to change its angle in Aaltitude relative to the turntable, and a motor on said turntable for adjusting said supporting means about said longitudinal and transverse axes. Y

8. In a mining apparatus, a wheel supported base adapted to run along a mine trackway, a

-horizontal turntableon said base, a kerll cutter,

an adjustable supporting structure intervening said turntable and kerf cutter and -adjustably mounted on said turntable, said turntable and supporting structure being adjustable to move said kerf cutter into horizontal cutting positions at any desired location between the mine roof and mine bottom and said supporting structure including supporting means adjustable bodily relative to said turntable and including supporting elementsadjustablesabout longitudinal and transverse axes to move -said'kerf cutter relative to the turntable into a vertical cutting position and to tilt the kerf cutter, when in horizontal cutting position, about a transverse axis to change its angle in altitude relativeto the turntable, and

said kerf cutter being adjustable in'to aforesaid horizontal cutting positions and said tilted position while the turntableremains stationary, and a motor on said turntable for adjusting said supporting means about said longitudinal and transverse axes.

9. In a mining apparatus, a wheel supported base adapted to run along a mine trackway, a horizontal turntable on said base, a kerf cutter, andan adjustable supporting structure intervening said turntable and kerl' cutter, said turntable and supporting structure being adjustable to move said kerf cutter into horizontal cutting positions at any desired ,location between the mine roof and e mine bottom and including supporting meansadjustable about longitudinal and transverse axes to move said kerf cutter relative to the turntable into a vertical cutting position and to tilt the ke'rf cutter about a transverse axis to change its angle in altitude relative vto the turntable, and said kerf cutter being adjustableinto aforesaid horizontal cutting positions and said tilted position while said turntable remains stationary and adjustable with the -turntable as the latter turns upon its axis into vertical cutting positions to cut vertical kerfs parallel with the4 trackway at any desired location` between the ribs of the entry.

ing said turntable and kerf cutter, said turntable 5 and supporting structure being adjustable to move said -kerf cutter into horizontal cutting positions at any desired location between the mine roof and mine bottom and including supporting means adjustable about'longitudinal and transverse axes- 10 to move said kerf cutter relative to the turntable into a vertical cutting position and to -tilt the kerf cutter about a transverse axis to change its angle in altitude relative to the turntable, and said kerf cutter being adjustable .into aforesaid horizontal l5 cutting positions and said tilted position while said turntable remains stationary and adjustable with the turntable as the latter turns upon its axis into vertical cutting positions to cut vertical kerfs parallel with the trackway at any desired .20

location between the ribs of the entry, said turnkerf at the level of the mine bottom outside and below the level ofthe mine trackwav. 25

. 11. In a mining apparatus, a portable base, an arm' structure swingable vertically relative to said base, a support pivotally mounted on said arm structure to swing relative thereto about a transverse axis, s aid support remaining stationary as 30 regards swing'iigmovement about its pivot relative to said arm' structure during vertical swinging of the latter, a cutter head rotatably mounted on said swingable support for rotation relative thereto, and a kerf cutter pivotally mounted on 35 said cutter head for swinging movement relative thereto.

12. In a mining apparatus, a portable base, an arm structurevfswingable horizontally and vertically relative4 to said base, a support pivotally 40 mounted on said arm structure to swing relative thereto when said arm structure is swinging or when it 'is stationary, a cutter head rotatably mounted -on said' swingable support for rotation relative thereto, and a kerf cutter pivotally 45 mounted on said cutter head Vfor swinging movement relative thereto.

13. In a mining apparatus, a portable base, an arm structure pivotally mounted on said base to swing relative thereto, a support carried at the 50 outer extremity of said arm' structure, a cutt'er head rotatably mounted on said support, a kerf cutter on said'head, and a motor carried by said support for actuating said kerf cutter and for rotating said head relative to` said support. lili` 14. In a mining apparatus, a portable base, an arm structure pivotally mounted on said base to swing in vertical planes, a head rotatably mounted on said arm structure, a kerf cutter support pivotally mounted on said head to swing relative 00 thereto, a kerf cutter pivotally mounted on said support to swing relative thereto, and devices for swinging said arm structure, for rotating said head and for swinging said cutter support and including a common drive shaft journaled within 55 said arm structure.

15. In a mining apparatus, a portable base, an arm structure pivotally mounted on said b ase to swing in vertical planes, a head rotatably mounted on said arm structure, 'a kerf cutter supportl 70 pivotally mounted on said head to swing relative thereto, a kerf cutter pivotally mounted on said support to swing relative thereto, and motor operated devices for swinging said arm structure,

for rotating said head and for swinging said cutl ter support relative to said head, said devices including a common driving motor on said base.

16. In a mining apparatus, a portable base, an arm structure pivotally mounted on said base, a head rotatably mounted on said arm structure, a kerf cutter support pivotally mounted on said head to swing relative thereto, a kerf cutter pivcarried by said arm structure and by which saidkerf cutter is supported for adjustment relative to said arm structure into horizontal and vertical cutting positions, 'said arm structure being swingable as aforesaid relative to said base and said supporting structure being adjustable relative to said arm structure to position said keri cutter to cut horizontal kerfs at any desired lo- 'cation between the mine roof and mine bottom and parallel vertical kerfs at any desired location between the ribs of the entry.

18. In a mining apparatus, a portable base, an arm structure mounted' on said base to swing horizontally and vertically relative thereto, a kerf cutter, and an adjustable supporting structure carried by said arm structure and by which said kerf cutter is supported, said arm structure being'swingable as aforesaid relative to said base and said supporting structure being adjustable relative to said arm structure to position said kerf cutter to cut horizontal kerfs at any desired location between the mine roof and mine bottom and parallel vertical kerfs at any desired location between the ribs of the entry, said adjustable supporting structure including means for tilting said kerf cutter about a transverse axis parallel toits cutting planes.

19. In a mining apparatus, a portable base, an arm structure mounted on said base to swing horizontally and verticallyrelative thereto, a kerf cutter, and .an adjustable supporting structure carried by said arm structure and by which said kerf cutter is supported, said arm structure being swingable as aforesaid relative to said base and said supporting structure being adjustable relative to said arm structure to position said kerf cutter to cut horizontal kerfs at any desired location -between the mine roof and mine bottom and parallel vertical kerfs at any desired location between the ribs of the entry, said adjustable supporting structure including means fortilting said keri' cutter about transverse and longitudinal axes parallel to its cutting planes.

20. In a mining apparatus, a wheel supported base adapted to run along a mine trackway, an

arm structure mounted on said base to swing horable as aforesaid relative to said lbase and saidV supporting structure being adjustable relative to said arm-structure to position said keri cutter Ato cut horizontal kerfs at any desired location between the mine roof and mine bottom, to cutv a. horizontal kerf at the level of the mine bottom outside yand below the level of the minetrackway and parallel vertical kerfs at any desired location between the ribs of the entry.

21. In aV mining apparatus, a portable base, a horizontal turntable on said base, a motor on said turntable, an arm. pivotally mounted on said turntable to swing in a vertical direction relative thereto, a frame rotatably mounted on said arm about an axis extending longitudinally of said arm and at all times at right angles to the-arm pivot axis, a kerf cutter support pivotally mounted on said rotatable frame to swing relative thereto about an axis at right angles to the lframe axis, and devices driven by said motor for swinging said arm, for rotating said frame and for swinging said cutter support.

22. In a mining apparatus, a portable base, a horizontal turntable on said base, a motor on Asaid turntable, an arm pivotally mounted on said turntable to swing in a vertical direction relative thereto, a frame rotatably mounted on said arm about an axis extending longitudinally of said arm and at right angles to the arm pivot axis, a kerf cutter support pivotally mounted on said rotatable frarne to swing relative thereto about an axis at right angles to the frame axis, a kerf cutter vmounted on said turntable at the forward end of said base and extending forwardly in advance of saidbase, said arm structure swingable about a horizontal axis in a vertical direction relative to said turntable and base, a support pivotally mounted on the outer extremity of said arm structure to swing through a relatively wide range rel--v ative thereto aboutan axis parallel with the arm structure axis while said arm remains stationary as'regards vertical swinging movement, and a kerf cutter pivotally mounted on said support to swing relative thereto about an axis angularly disposed with respect to said support axis, said support being swingable relative to said arm to move the kerf cutter into cutting positions at substantial angles at opposite sides of a plane including the support axis.

24. `In a mining apparatus, a portable' base, an arm structure pivotally mounted on the forward end of said base and extending forwardly in advance of said base, said arm structure swingable about a horizontal axis in a vertical direction relative to said base, a frame mounted on said arm structure vfor rotation relative thereto about an axis extendinglongitudinally of the arm structure, a support pivotally mounted on said frame to swing relative thereto about an axis at right angles to the frame axis, anda kerf cutter pivotally mounted on said support for swinging move.- ment relative thereto about an axis at right angles to said support axis.

25. In a mining apparatus, a portable base, an arm structure pivotally mounted on the forward end of said base and extending forwardly in advance of said base, said arm structure swingable about a horizontal axis in a vertical direction relative to said base, a frame mounted on said arm structure for rotation relative thereto about an axis Aextending longitudinally of the arm structure, a support pivotally mounted on said frame to swing relativethereto about an axis at right angles tothe frame axis, and a kerf cutter pivotally mounted on said support for swinging movement relative thereto about an axis at right angles to said support axis, said support axisbeing parallel with said arm structure axis when said kerf cutter is in a horizontal cutting position.

26. In amining apparatus, a portable base, an arm structurepivotally mounted on the forward end of said base and extending forwardly in advance of said base, said arm structure swingable about a horizontal axis in a vertical direction relative to said base,'a frame mounted on said arm structure for rotation relative thereto about an axis extending longitudinally of the arm structure, a support pivotally mounted on said frame' to swingl relative `thereto about an axis at right anglesto the frame axis, anda kerf cutter pivotally mounted on said support for swinging movement relative thereto about an axis at right angles to said support axis,` said support axis being parallel with said arm structure axis when said ker! cutter is in a horizontal cutting` position and said support axis, when said ker! cutter is in a vertical cutting position, extending at right angles to said arm structure axis. f

27. In a mining apparatus, a wheeled truck adapted to lrun along a mine ltrackwa'y, an arm structure pivotally mounted on the forward end of said truck and extending forwardly in advance o! said truck, saidarm structure swingablein a vertical direction relative to the truck about av driven by said motor !or swinging said support relative to said arm structure irrespective o! the swinging o! the latter, and devices driven by said motor for swinging said ker! cutter relative to said support.

30; Ina mining apparatus, a portable base, a horizontal turntable on said base. ka motor on said turntable, an arm structure pivotally mounted at the forwardA edge of said turntable and extending forwardly in advance o'f said base, said arm structure swingable in a vertical direction relative to the turntable about a horizontal axis, a frame mounted on said arm structure for rotation relative thereto about an axis extending longitudinally of said arm structure, a support pivotally mounted on said frame, a ker! cutter pivotally mounted on said support to swing relative thereto, devices driven by said motor for swinging said arm structure, devices actuated by said motor for ro' tating said frame relative to said arm structure,

devices driven by said' motor for swinging said rection relative thereto, said arm structure swingable relative to said motor, a frame mounted on said arm structure for rotation about the longitudinal axis of said arm structure, aiupport pivotally mounted on said frame at the forward horizontal axis4 located in advance of the front^-extrenuty of 'said am Structure a' ker! cutter truck wheel axes, a frame mounted on said arm structure for rotation relative thereto about an axis extending longitudinally o! said arm structure, va support pivotally mounted on said rotatable frame vat the forward extremity of -said arm structure, said support swingable relative to said frame about an axis at right angles to' the frame axis, and. a' ker! cutter pivotally mounted on said support.

28. In aV mining apparatus, a wheeled truck adapted to run along a mine trackway, an arm structure pivotally mounted onthe forward end of said truck and extendingforwardly in advance of said truck, said arm structure swingable in a vertical direction relativeto the truck about a horizontal axis located in advance of the'front truck wheel axes, a frame mounted on said arm structure for rotation relative thereto about an axis extending longitudinally of said` arm structure, a support pivotally mounted on said ro. tatable frame at the forward extremity o! said arm structure, said support swingable relative to said frame about an axis at right angles t'o the l frame axis, and a ker! cutter pivotally mounted on said supportto swing relative thereto about an axis extending at right angles to said support axis.

29. In a mining apparatus, a portable base, a horizontal turntable on xsaid base, a motoron said turntable, an arm structure pivotally 'mounted' on the forward -edge oi' said turntable to swing ina verticaldirection relative thereto about aA horizontal axis,said arm structure swingable relative to said motor, a support pivotally mounted on the outer extremity of saidarm structure to swing relative thereto about an axis parallel with the arm zstructure axis,a ker! cutter pivotally mounted on said supportto swing relative thereto, devices driven by said motor for swinging said arm structure relative to said turntable, devices cutter support.

pivotally mounted on said support to swing'relative thereto, devices driven by said motor for swinging said arm structure, devices driven by said motor for rotating said frame, devices driven by said motor for swinging said support, and

devices driven by said motor for swinging said kerf cutter relative to said support.

32. In a miningapparatus, a portable base, a horizontal turntable on said base, an arm structure pivotally mounted on said turntable to swing in a vertical vdirection relative thereto and extending forwardiy in advance of said base, a head mounted on said arm structure for rotation relative thereto aboutk the longitudinal axis o! said arm structure, a ker! cutter support pivotally mounted on said head, a ker! cutter lpivotally mounted on said support to swing relative thereto, motor operated devices carried by said arm structure for rotating said head, and motor operated devices carried by said head for swinging said 33. Ina mining apparatus, a portable base, a horizontal turntable on said base, an'arm structure pivotally mounted on said turntable to swing.

in a vertical direction relative thereto and extending !orwardly in advance o! said bese, ahead mounted on said arm structure for rotation rela-- tive thereto about the longitudinal axis o! said arm structure,- a ker! cutter support pivotally` mounted on said head, a ker! cutter pivotally .mounted on said support to swing relative thereto, motor operated devices carried by said arm structure for rotating said'head, motor operated devices carried by said head for swinging said cutf ter support, and motor operated devices' carried by said Icutter support torswingins midl ker! tending forwardly in advance of said base, a motor onsaid turntablerelative to which said arm structure is swingable, a head mounted on said arm structure to rotate relative thereto about the longitudinal axis of said arm structure, a'cutter support pivotally mounted on said head, a kerf cutter pivotally mounted on said cutter support to swing relative thereto, devices carried by said 1 turntable and driven by said motor for swinging said arm structure, devices driven by said motor and carried by said arm structure for rotating said head, and devices driven by said motor and 'carried by said head for swinging said cutter support.

35. In a mining apparatus, a portable base, a horizontal turntable on said base, an arm structure pivotally mounted on the turntable-to swing .in a vertical direction relative thereto and extending forwardly in advance of said base, a mo- I tor on said turntable relative to which said arm structure is swingable, a head .mounted on said arm structure torotate relative thereto about the longitudinal axis of, said arm structure', a cutter support pivotally mounted on. said head, a kerf cutter pivotally mounted onv said cutter support to swing relative thereto, devices carried by said turntable and driven by said motor for swinging said arm structure, devices driven by said motor and carried by said arm structure for rotating said head, devices driven by said'motor and carried by said head for swinging said cutter support, and devices driven by said motor and carried byfsaid support for swinging .said kerf cutter.

36. Ina mining apparatus, aportable base, an arm structure pivotally mounted on said base to swing in horizontal and vvertical directions relative thereto, a head mounted on said arm structure for rotation relative thereto about' the longitudinal axis of said arm structure, a cutter support pivotally mounted on said head, a kerf cutter pivotally mounted on said cutter support to swing relative thereto, motor operated devices for swinging said arm structure in aforesaid directions relative to said base, motor operated devices carried by said arm structure for rotating said head, and motor operated devices carried by said head for swinging said cuttersupport.

' 37. In a mining apparatus, a portable baseLan l arm structure pivotally mounted on said base to swing in horizontal and vertical directions relative thereto, a head mounted on said arm structure for rotation relative thereto about the lonv gitudinal axis of said arm structure, a cutter support'pivotally mounted on said head, a kerf cutter pivotally mounted on said cutter support to swing relative thereto, motor operated devic-es for swingingv said arm structure in aforesaid directions relative to said base, motor operated devices carried by said arm structure for rotating said' head, motor operated devices carried by said head for swinging said cutter support, and motor operated devices carried by said cutter support v for swingingr said kerf cutter.

` mounted on said arm structure to rotate relative thereto about the longitudinal axis of said arm structure, said head rotatable about an axis perpendicular to the axis of vertical swinging move.

ment of said arm structure, a cutter support pivaxis, and a kerf cutter pivotally mounted on said -support to swing .relative thereto about an axis at rightangles to the support axis.

39. In a mining apparatus, a portable base, lan arm structure pivotally mounted on said base to Swingin horizontal and vertical directions relative thereto, the axis of vertical swinging movement of said arm structure located a substantial distance in advance of the axis of horizontal swinging movement of said arm structure, a head mounted on said arm `structure to rotate relative theretoV about the longitudinal axis of said arm structure, said head rotatable about an axis perpendicular to the axis of vertical swinging movement of said arm structure, a cutter support pivotally mounted on said head to swing relative thereto about an axis at right angles to the head axis, a -kerf cutter pivotally mounted on said support to swing relative thereto about an axis at right angles to the support axis, and motor operated devices for swinging said arm structurek in 4thereto about the longitudinal axis of said arm structure, said head rotatable about an axis perpendicular to the axis of vertical swinging movevment of said arm structure, a cutter support pivotally mounted on said head to swing relative thereto about an axis at right angles to the head axis, a `kerf cutter pivotally mounted on said support to swing relative thereto about an axis at right angles to the support axis, motor opervated devices for swinging said arm stsucture in aforesaid directions relative to said base, and motor operated devices for rotating said head relative to said arm structure.

4l. In a mining apparatus, a portable base, an arm structure pivotally mounted on said base to swing in horizontal and vertical directions relative thereto, the axis ofv vertical swinging movement of said arm structure located a substantial distance in advance of the axis of horizontal swinging movement of said arm structure, a head mounted on said arm structure to rotate relative thereto about the longitudinal axis of said arm structure, said head rotatable about an axis perpendicular to the axis'of vertical swinging movement of said arm structure, a cutter support pivotally mounted on said head to swing relative thereto about an axis at right angles to the head axis, a kerf cutter pivotally mounted on said support to swing relative thereto about an axis at right angles to the support axis, motor operated devices for swinging said arm structure in aforesaid directions relative to said base, motor operated devices for rotating said head relative to said arm structure, and motor operated devices for swinging said cutter support relative to said head;

42. In a mining apparatus, a portable base, an arm structure pivotally mounted on' said base to swing in horizontal and vertical directions relative thereto, the axis of vertical swinging movement of said arm structure located a substantial distance in advance of the axis of horizontal swingingmovement of said arm structure, a head mounted on said arm structure to rotate relative thereto aboutthe longitudinal axis of said arm structure, said head rotatable about an axis perpendicular to the axis of vertical swinging movemont of said arm structure, a, cutter support pv-l otally mounted on said head to swing relative thereto about an axis at right angles to the head axis, a kerf cutter pivotally mounted on said support to swing relative thereto about -an axis at right angles to the support axis, motor operated devices for swinging said arm structure in aforesaid directions relative to said base, motor operated devices for rotating said head relative to said arm structure, motor operated devices for swinging said cutter support relative to said head, and motor operated devices for swinging said herr cutter relative to said cutter support.

43. In a mining apparatus, a portable base, an arm structure pivotally mounted on said base to swing in horizontal and vertical directions relative thereto, said arm structure extending forwardly in advance of said base, the axis of vertical swinging movement of said arm structure located a substantial distance in advance of the axis of horizontal swinging movement of said arm structure, a head rotatably mounted on said arm structure, a cutter support swingably mounted on said head to swing relative thereto, and a kerf cutter swingably mounted on said cutter support to swing relative thereto.

44. In a mining apparatus, a portable base, an arm structure pivotally mounted on said base to swing in horizontal and vertical directions relative thereto, said armstructure extending forwardly in advance of said base, the axis oi.' vertical swinging movement of said arm structure located a substantial distance in advance of the axis of horizontal swinging movement of said arm structure, ahead rotatably mounted on said arm structure, a cutter support swingably mounted on said head to swing relative thereto, and a kerf cutter swingably mounted on said cutter support to swing relative thereto, said head rotating relative to said arm structure about an axis extending longitudinally of said arm structure.

45. In a mining apparatus, a portable base, an arm structure pivotally mounted on said base to swing in horizontal and vertical directions relative thereto, said arm structure extending for- Wardly in advance of said base, the axis of vertical swinging movement of said arm structure located a substantial distance in advance of the axis of horizontal swinging movement or said arm structure, a head rotatably'mounted on said arm structure, a cutter support swingably mounted on said head to swing relative theretofand a kerf cutter swingably mounted on said cutter support to swing relative thereto, said head rotating relative to said arm structure about an axis extending longitudinally of said arm structure and the swing axis of said cutter support arranged at right angle's to the head axis.

46. In a mining apparatus, a portable base, an arm structure pivotally mounted on said base to swing in horizontal and vertical directions relative thereto, said arm structure extending .forwardly in advance of said base,the axis of vertical swinging movement of said arm structure located a substantial distance in advance cutter support to swing relative thereto. said head rotating relative to said arm structure about an axis extending longitudinally o! Said arm structure and the axis of said cutter support arranged at right angles to the head axis, the support axis extending parallel with the axis of vervstructure for rotation about the longitudinal axis of said arm structure, a support swingably mounted on said frame to swing relative thereto about an axis at right angles to the frame axis, and a kerf cutter pivotally mounted on 4said support to swing relative thereto about an axis at right angles to the support axis.

48. In a mining apparatus, a portable base, 'an arm structure pivotally mounted on said base to swing in horizontal andvertical directions relative thereto, said arm structure extending forwardly in advance of said base, the axis of vertical swinging movement of said arm structure located a substantial distance in advance of the axis of horizontal swinging movement of said arm structure, the axis of vertical swinging movement of said arm structure located in advance of said base, a vframe mounted on said arm structure forI rotation about the longitudinal axis of said arm structure, a supportswingably mounted on said frame to swing relative thereto about an axis at right angles to the frame axis, and a ke'rf cutter pivotally mounted on said support to swing relative thereto about an axis at right angles to the support axis.

49. In a. mining apparatus, a portable base, a horizontalturntable on said base, said turntable rotatable about a vertical axis, an arm structure pivotally mounted at the forward'edge of said turntable to swing upward and downwardly in a vertical direction relative thereto about a horizontal axis located in advance of said turntable, a frame mounted on said arm structure to rotate relative thereto about the longitudinal axis of said arm structure, a support swingably mounted on said frame to swing relative thereto, and a kerl cutter pivotally mounted on said support to swing relative thereto.

50. In a mining apparatus, a portable base, an arm structure pivotally mounted on said base to swing relative thereto, said arm structure extending longitudinally in advance of said base. a head mounted on said arm structure vfor rotation about the longitudinal axis of Said arm structure, said head rotatable about an axis perpendicular to the axis of swinging movement of said arm structure, a cutter support pivotally mounted on said head for swinging movement relative thereto, a kerf cutter pivotally mounted .on said cutter support for swinging movement relative thereto, said cutter support being swingable about its pivot relative` to said head to move said kerf cutter into relatively inclined cutting planes, and motor operated devices for swinging said arm structure, for rotating said head and for swinging said cutter support and said kerf cutter about their respective pivots, said cutter support swinging ldevices including motor operated gearing carried by said head.

51. In a mining apparatus, a portable base, an

arm structure pivotally mounted on said base to swing relative thereto, said arm structure extending longitudinally in advance of said base, a head mounted on said arm structure for rotation about the longitudinal axis of said arm structure, said head rotatableabout an axis perpendic'ular to the axis of swinging movement of said arm structure, a cutter support pivotally mounted on said cutter head for swinging movement relative thereto, a kerf cutter` pivotally mounted on said cutter support for swinging movement relative thereto, said cutter support being swingable about its pivot relative to said head to move said kerf cutter into relatively inclined cutting planes, and motor operated devices for swinging said arm structure, for rotating said head and for swinging said cutter support and said kerf cutter about their respective pivots, said cutter support swinging devices including motor operated gearing carried by said head, and said kerf cutter swinging devices including motor operated gearing carried by said cutter support.

52. In a mining apparatus, a portable base, an arm structure pivotally mounted onl said base to swing in horizontal and vertical directions relative thereto, said arm structure extending longitudinally in advance of said base, a head mounted `on said arm structure for rotation about the longitudinal axis of said arm structure, said head rotatable about an axis perpendicular to the axis of vertical swinging movement of said arm structure, a cutter support pivotally mounted on said head for swinging movement relative thereto, a vertical kerf cutter pivotally mounted on said support'for swinging movement relative thereto, and motor operated devices for swinging said arm structure relative to said base, for rotating said head and for swinging said cutter support and said kerf cutter about their respective pivots, said support swinging devices including motor operated gearing carried by said head,

53. In a mining apparatus, a portable base, an arm structure pivotally mounted on said base to swing in horizontal and vertical directions relative thereto, said arm structure extending longitudinally in advance of said base, a head mounted on said arm structure for rotation about the longitudinal axis of said arm structure, said head rotatable about an lairis perpendicular to the axis of vertical swinging movement of said arm structure, a cutter support pivotally mounted on said head for swinging movement relative thereto, a vertical kerf cutter pivotally mounted on said support for swinging movement relative thereto, and motor operated devices for swinging said arm structure relative to said base, for rotating said head and for swinging said cutter support and said kerf cutter about their respective pivots, said support swinging devices including motor operated gearing carried by said head, and said kerf cutter swinging devices including motor operated gearing carried by said cutter support.

54. In a mining apparatus, a portable base, a horizontal turntable mounted on said base for rotation about a vertical axis, an arm structure pivotally mounted on said turntable for vertical swinging movement relative thereto abouta horizontal axis, a head mounted on said arm structure for rotation relative thereto about the-longitudinal axis of said arm structure, said head ro-i tatable about an axis perpendicular to said arm structure axis of vertical swinging movement, a

cutter support pivotally mounted on said head for swinging movement relative thereto, a ker cutter pivotally mounted on said support for swinging movement relative thereto, and motor operated said arm structure relative to said turntable, for

rotating said head and for swinging said cutter support and kerf cutter about vtheir respective pivots, said head rotating devices including motor operated gearing carried by said arm structure.

55. In a mining apparatus, a portable base, a horizontal turntable mounted on said base for rotation about a vertical axis, an arm structure pivotally mounted on said turntable for vertical swinging movement relative thereto about a horizontal axis, a head mounted on said arm structure for rotation relative thereto about the longitudinal axis of said arm structure, said head rotatable about an axis perpendicular to said arm structure axis of vertical swinging movement,` a cutter support pivo-tally mounted on said head for swinging movement relative thereto, a kerf cutter pivotally mounted on said support for swinging movement relative thereto, and motor operated devices for rotating said turntable, for swinging saidlarm structure relativeto said turntable, for rotating said head and for swinging said cutter support and kerf cutter about their respective pivots, said head rotating devices including motor operated gearing carried by said arm structure, and said cutter support swinging devices including motor operated gearing carried by said head.

56. In a mining apparatus, a portable base, a A

horizontal turntable mounted on said base for rotation about a vertical axis, ,an arm structure pivotally mounted on said turntable for vertical swinging movement relative thereto about a ,hori-v zontal axis, a head mounted on said arm structure for rotation relative thereto about the longitudinal axis of said. arm structure, said head rotatable about an axis perpendicular to said arm structure axis of vertical swinging movement, a cutter support pivotally mounted on said head for swinging movement relative thereto, a kerf cutter pivotally mounted on said support for swinging movement relative thereto, and motor operate-d devices for rotating said turntable, for swinging said arm structure relative to said turntable, for rotating said head and for Iswinging said cutter support and kerf cutter about their respective pivots, said head rotating devices including motor operated gearing carried by, said arm structure, said cutter support swinging devices including motor operated gearing carried by said head, and said kerf cutter swinging devices including motor operated gearing carried by said v cutter support.

' 57. In a mining apparatus, a portablebasaean arm structure pivotally mounted on said base for swinging movement in a plurality of angularly related directions relative thereto, said arm structure extending longitudinally in advance of said to about an axis at right angles to the head axis.

58. In av mining'apparatus, a portable base. y

an arm structure pivotally mounted on said base for swinging movement relative thereto, said arm vstructure extending longitudinally in advance of said base, a support pivotally mounted .on the outer extremity of said arm structure for swinging movement relative thereto about an axis parallel with the arm structure pivot axis, a cutter head mounted on said support for rotation relative thereto about an axis extending perpendicularly `to said support axis, a kerf cutter pivotally -said base, a support pivotally `mounted 'on the outer extremity of said arm'struoture for swinging movement relative thereto about an axis parallel with the arm structure pivot axis, a cutter -head mounted on said support for rotation relative thereto about anaxis extending perpendicularly 'to said support axis, a kerf cutter pivotally mounted on said cutter head for swinging movement relative thereto about an axis at right angles to the head axis, and motor operated devices for swinging said arm structure relative to said base, for independently swinging said support relative to said arm structure, for rotating said head relative to said support and for swinging said 'kerf cutter relative to said head, said arm structure swinging devices including motor operated gearing carried by said base.

60. In a mining apparatus, a portable base, an arm structure pivotally mounted on said base for swinging movement relative thereto, said arm structure extending longitudinallyy in advance of said base, a support pivotally. mounted on the outer extremity of said arm structure for swinging movement relative thereto about an axis parallel with the arm structure pivot axis, a cutter head mounted on said support for rotation relative thereto about an axis extending perpendicularly to said support axis, a kerf cutter pivotally mounted on said cutter head for swinging move'- ment relative thereto about an axis at right angles to the head axis, and-motor operated devices for swinging said arm structure relative to said base, for swinging said support relative to'said arm structure, for rotating said head relative to said support'and for swinging said kerf cutter relative to said head, said arm structure swinging devices including motor operated gearing carried by said base, and said support swinging devices including other motor operated gearing carried by said arm structure.

81. In a mining apparatus, a an arm structure pivotally mounted on said base for swinging movement relative thereto, said arm structure extending longitudinally in advance of said base, a support pivotally mounted on` the outer extremity of said arm structure for swinging movement relative thereto about an axis parallel with the arm structure pivot axis, a cutter head mounted on said support for rotation relative thereto about an axis extending perpendicularly to said support axis, a kerf cutter pivotally mounted on saidv cutter head for swinging movement relative thereto about an axis at right angles to the head axis, and motor operated de- Yportable base,

for swinging movement relative thereto, said arm structure extending longitudinally in advance of said base, a support pivotally mounted on the outer extremity of said arm structure for swinging movement relative thereto about an axis parallel with the arm structure pivot axis, a cutter head mounted on said support for rotation relative thereto about an axis extendingperpendicularly to said support axis, a kerf cutter pivotally mounted on said cutter head for swinging movement relative thereto about an axis ,at right angles to the head axis, and motor operated devices for swinging said arm structure relative to said base, for swinging said support relative-to said.

arm structure, for rotating said head relative to said support and for swinging said kerf cutter relative to said head, said arm structure swinging devices including motor operated gearing carried `by said base, said support swinging devices including other motor operated gearing carried by said arm structure, and said head rotating devices and saidkerf cutter swinging devices including motor operated gearing carried by said head. l

63. In a mining apparatus, a portable base, an arm structure pivotally mounted on said base to swing in a vertical direction relative thereto, said arm being disposable in .a position extending lengthwise of'said base and in a position at right angles to the longitudinal axis of said base, a cutter frame mounted on the outer extremity of said arm structure for rotation relative thereto independently of arm structure swing, a cutter support pivotally mounted on seald cutter frame to swing relative thereto about a transverse axis, and a kerf cutter pivotally mounted on said cutter support to swing relative thereto.

64. In a mining apparatus, a portable base, an arm structure pivotally mounted on said base to swing in a vertical direction relative thereto, said arm being disposable in a position extending lengthwise of said base and in right angle positions at either side of said base, a cutter frame mounted on the outer extremity of said arm structure for rotation' relative thereto independently of arm structure swing, a cutter support pivotally mounted on said cutter frame to swing relative thereto about a transverse axis,

and a kerf cutter pivotally mounted on said cutter support to swing relative thereto.

65. In a mining apparatus, a portable base, an arm structure pivotally mounted on said base to swing in a vertical direction relative thereto about a horizontal axis extending transversely of said base,-said arm structure extending lengthwise of said base,ja cutter frame mounted on the outer extremity of said arm structure for rotation relative thereto independently of arm structure swing, a cutter support pivotally mounted on said cutter frame to swing relative thereto about a transverse axis, a kerf cutter pivotally mounted on said 'cutter support to swing relative thereto, a motor, means driven by said motor for actuating said kerf cutter, and means driven by said m'otor for swinging said cutter support relative to said rotatable Jcutter frame.

66. In a mining apparatus, a portable base, an arm structure pivotally mounted on said base to swing in a vertical direction relative thereto about a horizontal axis extending transversely of said base, said arm structure extending lengthwise of said base, avcutter frame mounted on the outer extremity of said arm structure for rotation relative thereto independently of arm struc- .ture swing, a cutter support pivotally mountedv on said cutter frame, a kerf cutter pivotally mounted on said cutter support to swing relative thereto, a motor, means driven by said motor for of said base, a cutter frame mounted on the outer extremity of said arm structure for rotation relative thereto about an axis extending longitudinally of said arm structure, a cutter support pivotally mounted on said cutter frame, a kerf cutter pivotally mounted on said cutter support for swinging movement relative thereto, -a motor, means driven by said motor for actuating said kerf cutter, means driven by said motor for swinging said cutter support relative to said rotatable cutter frame, and means driven by said motor for swinging said arm structure relative to said base.

63. In a mining apparatus, a portable base, an arm structure pivotally mounted on said base to swing in a vertical direction relative thereto about a horizontal axis extending transversely of said base, said arm structure extending lengthwise of said base, a cutter frame mounted on the outer extremity of said arm structure for rotation relative thereto about an axis extending longitudinally of said arm structure disposed at right angles to the pivotal axis of said arm structure, a cutter support pivotally mounted on said cutter frame, a kerf cutter pivotally mounted on said cutter support for swinging movement relative thereto, a

motor, means driven by said motor for actuating said kerf cutter, means driven by said motor for swinging said cutter support relative to said rotatable cutter frame, and means driven by said motor for swinging said arm structure. relative to said base.

69. In a mining apparatus, a portable base, an

larm structure pivotally mounted on said base to swing in a vertical direction relative thereto about a horizontal axis extending` transversely of said l base, said arm structure extending lengthwise of means driven by said motor for swinging said y arm structure relative to said base.

70. In a mining apparatus, a portablebase, an arm structure pivotally mounted on said base to swing in a vertical direction relative thereto about a horizontal axis extending transversely of said base, said arm structure extending lengthwise of said base, a cutter frame mounted on the outer extremity of said arm structure for rotation relative thereto about an axis extending longitudinally of said arm structuraafvcutter support pivotally mounted on said cutter frame f or swinging movement relative thereto about an axis at right angles to the cutter frame axis, a kerf cutter pivotally mounted on said cutter support for swinging y movement relative thereto, said support axis when said kerf cutter is in horizontal cutting position extending parallel with said arm structure axis, a motor, means driven by said motor for actuating said kerf cutter, means driven by said motor for swinging said cutter support relative to said rotatable cutter frame, and means driven bysaid motor for swinging saidarm structure'relative to said base.

7l. In a I mining apparatus, a portable base, an arm' structure comprising but a single rigid arm pivotally mounted on said base to swing in a vertical direction relative thereto, a frame mounted on'said arm for rotation relative thereto, a cutter support pivotally mounted on said rotatable frame to swing relative thereto about a transvlerse axis, said cutter support being swingable through at least relative to said frame., a keri cutter plvu otally mounted on said cutter support to swing relative thereto, and means for swinging said arm structure and cutter support about their respec- -tive pivots and for' rotating said frame relative to said arm structure.

72. In ,a mining apparatus, ajportable base, an arm structure comprising but a single rigid arm pivotally mounted on said base to swing in a vertical direction relative thereto, a frame mounted on said arm for rotation relative thereto, avcutter, support pivotally mounted on said rotatable frame to swing relative thereto about a transverse axis, said cutter support being swingable through an angle substantially greater than 90 relative to said frame, a kerf cutter pivotally mounted on said cutter support to swing relative thereto, and means for swinging said arm structure and cutter support about their respective pivots and for rotating said frame relative tosaio. arm structure.

73. In a -mining apparatus, a portable base, a horizontal turntable on said base, en arm pivotally mounted on said turntable to swing in a vertical direction relative thereto about a transverse axis, a cutter supportpivotally mounted on the outer extremity of said arm to swing relative thereto about an axis parallel with the arm pivot axis, a horizontal kerf cutter carried by said cutter support, and means for swinging said cutter support about its pivot relative to said arm to horizontal planes including horizontal planesV above andbelow said turntable while the kerf cutter at all times remains in a substantially horizontal cutting position.

74. In a mining apparatus, a portable base, a horizontal turntable on said base, anarm pivotally mounted on said turntable to swing in a vertical direction relative thereto about a transverse 

